This invention relates to vehicle engine shutter assemblies. Vehicle shutter mechanisms are commonly mounted adjacent to and parallel a vehicle engine radiator, to control air flow through the radiator and thereby regulate engine temperature. Typical shutter mechanisms are disclosed in U.S. Pat. Nos. 2,248,094 to Kysor, 2,805,027 to Ferris, 3,198,298 to Ferris, and 3,759,054 and 3,759,056 to Graber. Such mechanisms are rather complex and sophisticated, typically having more than 100 component parts. The mechanism is composed of fabricated metal vanes, frames and operators, providing variable shutter positions over a wide range from fully open to fully closed, to achieve highly controlled air flow rates. As such, the mechanism is also relatively expensive and typically used only on large truck tractors where the expense is fully justified. The mechanism is rarely used on smaller vehicles such as automobiles. Yet, the use of a shutter system on automobiles would improve efficiency of operation.
Moreover, in the development of the present invention, it was determined that the appropriate shutter assembly can serve other purposes too. Some modern automobiles have considerable engine compartment sound insulation in efforts to reduce noise transmission to a fraction of the original level. This is especially useful for diesel engines, particularly when cold, because the engine clatter is then at a maximum. In spite of the engine compartment sound insulation now used, however, there is considerable engine noise transmitted through the front of the compartment, i.e., through the radiator. This noise is particularly noticeable when the vehicle is at a standstill or slowly moving, e.g., in heavy traffic. Obviously, large quantities of air must be caused to flow through openings in the radiator under normal driving conditions, but at idling speeds, such air flow is not necessary. The present invention achieves noise abatement and aerodynamic drag reduction as well as engine temperature control.